Grant: Collaborative Research and Development Grants

Waste Management (WM) operates several landfills in Canada and leachate generation is quite important in some old sites, particularly in cells that were capped following the now-outdated Quebec's landfill regulation. The latter did not require final covers to create an impedance to seepage of water through the cover, thereby reducing leachate generation. Leachate is expensive to collect and treat, and its presence may disturb waste decomposition and clog biogas wells screens. The central theme of this project is leachate generation reduction. This is usually achieved by appropriate cover design. But, irrelevant of design and materials, effectiveness of the design has to be assessed by proper measurement of seepage over time. In this project, we will test the reliability of lysimeters to assess infiltration in the field. This is fundamental to give credibility to the exercise of assessing the effectiveness of any final cover design. As far as design and materials are concerned, we will evaluate the behaviour of contaminated soils as part of cover systems and their impact on the surrounding environment. The goal is to open new avenues for their beneficial reuse, which is strategic for WM and to the landfilling industry at large. In addition to the formation of highly qualified personnel in this important area of civil engineering, there are important practical, economical and scientific outcomes to expect from this partnership with WM, including: significant reduction in leachate treatment costs, development of new final cover strategies, and documentation of large-scale lysimeters and of unsaturated flow through final covers.